# Parameter encoding

## The `allowReserved` setting

OpenAPI 3.x supports the `allowReserved` setting, which applies exclusively to query parameters. This allows reserved characters, such as `:/?#[]@!$&'()*+,;=`, to appear unencoded in request URLs.

OpenAPI 3.x does not support the `allowedReserved` setting for path parameters, although API owners may occasionally want to model this behavior. Consider a URL with a path parameter `item`, such as `https://stuff.com/store/{item}`. The API might be designed to accept values like `most-popular` or `book/most-popular` for `{item}`, where the `/` character remains unencoded, resulting in a URL like `https://stuff.com/store/book/most-popular`.

The Speakeasy OpenAPI extension `x-speakeasy-param-encoding-override: allowReserved` can be applied to a path parameter to allow reserved characters, such as `:/?#[]@!$&'()*+,;=`, to appear unencoded in the URL.

Here's an example demonstrating the use of the path parameter encoding extension:

```yaml
  /store/{item}:
    get:
      operationId: item
      parameters:
        - name: item
          in: path
          schema:
            type: string
            example: most-popular
          required: true
          x-speakeasy-param-encoding-override: allowReserved
      responses:
        "200":
          ...
```

As of November 2024, the `x-speakeasy-param-encoding-override` extension is supported for Java. Contact support for availability in other languages.